Hello, Been reading through the Wiki and FAQ documentation on the SQLite site, and I have one point of confusion.... In an earlier email, I was given some great numbers indicating that, although SQLite locks an entire DB file, the speeds were pretty impressive (given my read of the numbers you gave me) and would be fine. But I then read some info on the use of Transactions and some detail on the locking behavior, and I'm confused.... As I read it, SQLite locks the database file as a whole, thus encouraging the use of several DB files to minimize multi-user delays. But then I put that in context of the notes on using Transactions....
Why the heck would anyone even need Transactions in the first place? If the DB file is locked, no changes can be made, right? So I'm wondering if I am missing a few pieces.... Is the database file locked more than once during a process? That is, does it get locked as the Update statement is getting a collection of rows with which to apply the intended actions? Does it then release the lock as it prepares the update on this subset of data, and then re-lock when it prepares to write? If so, that would explain the need for a Transacction, as it leaves gaps of access during the transaction. If not, then I am mystified.... My concern stems from my experience with my day job's T-SQL server where there are occasional Select stored procedures and some stored procedures with both Select and Update/Insert blocks that take as long as a minute or two to process. We have some clients represented in our database with years of clientele, and with hundreds of customers per week or even per day. Ignoring Transactions for a second, if I have such a Select, will every user ben locked behind a wall until the Select for user 1 is complete? And if this is not the case for Select, will it be so for Update/Insert of this lenth? My uses of SQLite, via the upcoming PHP5, are not intended for any such huge database extremes, but as in my earlier email, I do want to get a better grasp of its limitations. Since no public server is yet serving PHP5 pages (still in Beta), I can't really test it myself. Thanks for taking the time to help, _______________ Vania Smrkovski -- Vania Smrkovski http://www.pandorasdream.com --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
